1. Field of the Invention
This invention relates to a receiver tank for use in a refrigeration cycle, a heat exchanger with a receiver tank, and a condensing apparatus for use in a refrigeration cycle, which can be applied to an air-conditioning system for automobile use, household use and business use.
2. Description of Related Art
FIG. 22 shows an expansion-valve system refrigeration cycle as one of typical refrigeration cycles. In the refrigeration cycle, the gaseous refrigerant of high temperature and high pressure sent out from a compressor CP is introduced into a condenser CD and exchanges heat with the ambient air to be cooled and condensed therein. The condensed refrigerant mostly in a liquefied state flows into a receiver-tank RT to be completely separated into a gaseous refrigerant and a liquefied refrigerant. Then, only the liquefied refrigerant flows out of the receiver-tank RT. The liquefied refrigerant is decompressed and expanded quickly by an expansion-valve EV, and is introduced into an evaporator EP as a mist-like refrigerant of low pressure and low temperature. This mist-like refrigerant evaporates in the evaporator EP by absorbing latent heat from the ambient air to be turned into a gaseous refrigerant. Then, the gaseous refrigerant flows out of the evaporator EP, and is inhaled by the compressor CP.
In FIG. 22, the spotted area indicates that a refrigerant is in a liquid state. In the meantime, the refrigeration flow rate is controlled by adjusting the opening degree of the expansion-valve EV in response to the signal sent from a heat-sensitive-coupler SC provided at the outlet side of the evaporator EP.
By the way, in a refrigeration cycle for automobile use, it is proposed that a refrigerant condensed in a condenser CD is subcooled to a temperature lower than the condensation temperature of the refrigerant by about several degrees to increase the amount of heat release and thereafter the subcooled refrigerant is introduced into an expansion-valve EV and an evaporator EP to enhance the refrigerating capacity. Concretely, the subcooling portion, which subcools the refrigerant condensed by the condenser CD to a temperature lower than the condensation temperature of the refrigerant by several degrees centigrade, is provided so as to send the condensed refrigerant to the evaporator side as a stabilized liquid refrigerant. Usually, this subcooling portion is arranged at the downstream side of the receiver-tank RT. In many cases, such a subcooling portion is integrally provided to the condenser CD (subcool system condenser) in view of space efficiency.
On the other hand, in many cases, a receiver-dryer is used as the aforementioned receiver-tank RT. The receiver-dryer is provided with a desiccant-filled-portion therein to absorb the moisture components of the refrigerant. Such a receiver-dryer includes the so-called sandwich-type receiver-dryer having an upper space 33 above a desiccant-filled portion 32 and a lower space 34 below the desiccant-filled portion 32 in a vertical tank 31 as shown in FIGS. 23A-23C, and the so-called bag-type receiver-dryer provided with a desiccant-filled portion 32 in one side in a vertical tank 31 as shown in FIG. 23D.
In the receiver-dryer having a sucking-pipe 36 shown in FIG. 23A, the refrigerant flowed into the upper space 33 via the refrigerant inlet 35 passes through the desiccant-filled-portion 32 to reach the lower space 34. Then, the liquefied refrigerant separated from the gaseous refrigerant is sucked up by the sucking-pipe 36 and flows out of the refrigerant outlet 37 provided at the top of the tank.
In the receiver-dryer having a supplying-pipe 38 shown in FIG. 23B, the refrigerant introduced from the refrigerant inlet 35 provided at the bottom portion flows up the supplying-pipe 38 to reach the upper space 33, and then passes through the desiccant-filled-portion 32 to reach the lower space 34. Then, the liquefied refrigerant separated from the gaseous refrigerant flows out of the refrigerant outlet 37 provided at the bottom of the tank.
In the inlet-outlet-confrontation-type receiver-dryer shown in FIG. 23C, the refrigerant introduced into the upper space 33 via the top refrigerant inlet 35 passes through the desiccant-filled- portion 32 to reach the lower space 34. Then, the liquefied refrigerant separated from the gaseous refrigerant flows out of the refrigerant outlet 37 provided at the bottom of the tank.
In the bag-type receiver-driver shown in FIG. 23D, the refrigerant flowed into the tank via the refrigerant inlet 35 provided at the side portion of the tank contacts the desiccant-filed-portion 32, and the liquefied refrigerant separated from the gaseous refrigerant in the lower portion of the tank flows out of the refrigerant outlet 37 provided at the bottom of the tank.
In an air-conditioning system, it is always desired to improve the space efficiency and performance. Especially, in an automobile air-conditioner, in order to effectively use the limited body space, it is requested that the whole system be further miniaturized. In order to realize the aforementioned requests, it is necessary to reduce the amount of refrigerant sealed in the refrigeration cycle, to enhance the performance stability to load fluctuation (overcharge toughness) and to prevent performance deterioration with time due to a continuous running (decline of leakage toughness). For these purposes, it is desired to secure a steady region, i.e., a stable region in a subcooled state of the refrigerant to the amount of sealed refrigerant, as widely as possible.
FIG. 8 is a correlation characteristic figure showing the correlation between a subcooling degree of the condensed refrigerant and an amount of sealed refrigerant obtained by a charge examination (cycle bench) of an automobile air-conditioner. In this correlation characteristic figure, it is ideal that the rising curve is steep until it reaches a steady region as shown by the phantom-line curve X2 and that the steady region has a wider range.
However, in an automobile air-conditioner using a conventional subcooling system condenser, the rising curve is gentle until it reaches the steady region as shown by the solid-line curve Y. Therefore, the steady region starting point delays toward the larger amount of sealed refrigerant side, which results in a delayed refrigerant sealing timing and a narrow steady region width. This means that in the conventional automobile air-conditioner the miniaturization by decreasing the sealed refrigerant amount is difficult, the performance stability to load fluctuation is bad, and the performance tends to deteriorate with time due to a continuous running.
The inventors investigated causes of the above-mentioned problems of the conventional automobile air-conditioner from various aspects so as to realize a miniaturized high-performance automobile air-conditioner. Consequently, the inventors revealed that one factor of the above-mentioned problems resides in a structure of a conventional receiver-dryer RD. That is, since the interface between the liquefied refrigerant and the gaseous refrigerant, i.e., the surface of the liquefied refrigerant, near the refrigerant outlet of the receiver-dryer RD is hard to become stable, the stable supply of the liquefied refrigerant to the following cycle part cannot be performed. Furthermore, a large amount of gaseous refrigerant will be mixed into the liquefied refrigerant to be flowed out. Therefore, the above-mentioned steady region becomes narrower and the steady region starting point delays toward the larger amount of sealed refrigerant side.
That is, since a refrigerant flow velocity flowing into a receiver-dryer RD from a condenser CD is generally high, in a sandwich-type receiver-dryer, larger turbulence of the liquefied refrigerant occurs in the upper space 33 into which the refrigerant is introduced. Consequently, since the liquefied refrigerant stagnates in the upper space 33, the liquefied refrigerant is not fully supplied to the lower space 34. As a result, a few amount of liquefied refrigerant accumulated in the lower space 34 is disturbed by the high-speed liquid flow passed through the desiccant-filled-portion 32, which causes bubbles of gaseous refrigerant. For this reason, it is assumed that a gaseous refrigerant flows out of the refrigerant outlet 37 exposed to the gaseous phase due to large surface fluctuation, and/or a lot of air bubbles are involved into the liquefied refrigerant to be flowed out.
On the other hand, in the bag-type receiver-dryer, it is assumed that since the internal refrigerant flow velocity and the turbulence of the internal refrigerant are larger than in the sandwich-type receiver-dryer, the liquefied refrigerant surface near the refrigerant outlet 37 becomes further unstable, resulting in a larger outflow of gaseous refrigerant.
In view of the aforementioned technical background, the present invention has been made. It is an object of the present invention to provide a receiver-tank for a refrigeration cycle which is small in size, light in weight and small in refrigerant amount.
It is another object of the present invention to provide a receiver-tank for a refrigeration cycle which can enlarge the stable region of refrigerant to an amount of sealed refrigerant and supply the stable liquefied refrigerant to the following cycle portion.
It is still another object of the present invention to provide a condensing apparatus for use in a refrigeration cycle in which a surface of a liquefied refrigerant separated from a gaseous refrigerant can be stabilized and only the liquefied refrigerant can be supplied from the receiver-dryer to the subsequent cycle part.
It is still yet another object of the present invention to provide a receiver-dryer used for the above-mentioned condensing apparatus in which the surface of the liquefied refrigerant separated from the gaseous refrigerant can be stabilized and only the liquefied refrigerant can be supplied to the subsequent cycle part.
Another object of the present invention will be apparent from the following embodiments.
According to a first aspect of the present invention, a receiver-tank for use in a refrigeration cycle, wherein a condensed refrigerant is introduced into the receiver-tank and accumulated therein and only a liquefied refrigerant flows out of the receiver-tank, the receiver-tank comprises:
a tank main body having a refrigerant inlet and a refrigerant outlet each provided in a bottom wall of the tank main body;
a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer, the flow-resistance layer being provided in the tank main body such that an upper space is formed above the flow-resistance layer; and
a suction pipe provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the refrigerant outlet,
whereby a refrigerant introduced into the tank main body via the Refrigerant inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the refrigerant outlet via the suction pipe.
According to the first aspect of the present invention, the condensed refrigerant, which is a mixture of a gaseous refrigerant and a liquefied refrigerant, is abruptly diffused into a wide area of the inner bottom portion of the tank main body to thereby reduce the flow velocity immediately after introduced into the tank main body. Subsequently, the refrigerant goes up through the desiccant-filled-layer to further decrease the flow velocity.
Therefore, the liquefied refrigerant, which is slow in flow velocity as compared with a gaseous refrigerant, passes through the desiccant-filled-layer to reach the upper space, which causes a reduced flow velocity. Accordingly, the liquefied refrigerant accumulates to create liquid stagnation in the upper space without causing turbulence. On the other hand, the flow velocity of the gaseous refrigerant also abruptly reduces when the gaseous refrigerant passes through the desiccant-filled-layer.
For this reason, when the gaseous refrigerant reaches the liquid stagnation created in the upper space, it slowly goes up in the liquid stagnation as bubbles. Consequently, a gaseous refrigerant passes through the surface of the liquid stagnation and accumulates above the surface without disturbing the surface.
Since the upper end of the suction pipe is located at the bottom of the liquid stagnation stably accumulated in the upper space, only the accumulated liquefied refrigerant flows into the suction pipe to be discharged from the refrigerant outlet.
Since only the liquefied refrigerant stably flows out from the receiver-dryer as mentioned above, it becomes possible to fill an appropriate amount of refrigerant in the refrigeration cycle at an earlier stage. Moreover, since the steady region between the optimum point and the excessive point of refrigerant amount can be expanded by using the surplus space in the receiver-dryer as a buffer space, the whole refrigeration cycle can be operated stably.
In the first aspect of the present invention, it is preferable that the flow-resistance layer is provided with a plurality of dispersing passages for dispersing the refrigerant in a radial and outward direction of the tank main body. For example, the flow-resistance layer may be formed by numerous particles, knitted fabrics, woven fabrics, non-woven fabrics, a porous or perforated panel/member or the lamination thereof, or a combination of one or more of the aforementioned members/materials.
In the first aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents. That is, in a receiver-tank for use in a refrigeration cycle, desiccating agents are disposed in the receiver-tank in order to delete the moisture in a refrigerant. Accordingly, in the aforementioned structure, the flow-resistance layer can also be used as desiccating agents.
Furthermore, in the first aspect of the present invention, it is preferable that a lower space for diffusing the refrigerant introduced from the refrigerant inlet is formed under the flow-resistance-layer in the tank main body. In cases where the aforementioned structure is employed, a refrigerant introduced from the refrigerant inlet is diffused widely in the lower space, to thereby further reduce the flow velocity. Thus, occurrence of turbulence of refrigerant can be prevented effectively, resulting in a smooth creation of stable liquid stagnation.
Furthermore, in the first aspect of the present invention, it is preferable that a height of the lower space is 25% or less of a thickness of the flow-resistance layer. In this case, the lower space can be decreased while ensuring the flow decreasing function by the lower space. Therefore, turbulence of refrigerant hardly occurs, enabling an ample supply of liquid refrigerant to the upper space.
Furthermore, in the first aspect of the present invention, it is preferable that the suction pipe has an enlarged-diameter portion at an upper end thereof.
In this case, since the inlet side of the suction pipe forms a dented portion at the upper portion of the flow-resistance layer, the liquid refrigerant can be easily flowed into the suction pipe. Furthermore, the flow velocity of the liquefied refrigerant becomes slower than in a non-enlarged-diameter portion. Therefore, even if bubbles of the gaseous refrigerant exist in the enlarged-diameter portion, the bubbles can go up in the enlarged-diameter portion.
In order to enhance the function of the enlarged-diameter portion, in the first aspect of the present invention, it is preferable to employ the following structure.
That is, in the first aspect of the present invention, it is preferable that the following conditions are satisfied: d1 less than d2xe2x89xa63d1, and d1 less than h1xe2x89xa65d1, wherein an inner diameter of a non-enlarged-diameter portion of an intermediate portion of the suction pipe, the maximum opening diameter of the enlarged-diameter portion and a depth of the enlarged-diameter portion are defined by d1, d2 and h1, respectively.
Furthermore, in the first aspect of the present invention, it is preferable that an upwardly extended bubble-swallow-prevention wall is formed on a periphery of an upper end opening of the suction pipe. In this case, the bubbles of the gaseous refrigerant going up through the liquid stagnation created in the upper space will be hardly swallowed by the liquefied refrigerant flowing toward the suction pipe because of the existence of the bubble-swallow-prevention wall. Thus, it is possible to prevent the gaseous refrigerant from being swallowed into the suction pipe.
In order to enhance the function of the bubble-swallow-prevention wall, in the first aspect of the present invention, it is preferable to employ the following structure.
That is, in the present invention, it is preferable that the following conditions are satisfied: h2 less than 2d1, wherein an inner diameter of a non-enlarged-diameter portion of an intermediate portion of the suction pipe and a height of the bubble-swallow-prevention wall are defined by d1 and h2, respectively.
Furthermore, in the present invention, it is preferable that the following conditions are satisfied: 1.5xcfx86xe2x89xa6L1xe2x89xa60.8D, wherein a distance between a center of the receiver-tank outlet and a center of the receiver-tank inlet, an inner diameter of the tank main body and an opening diameter of an outlet opening of the receiver-tank inlet are defined by L1, D and xcfx86, respectively.
In this case, since the distance between the refrigerant inlet and the refrigerant outlet can be kept appropriately, it becomes possible to prevent the upstream of the refrigerant introduced from the refrigerant inlet from being biased toward the refrigerant outlet side, or the suction pipe side, resulting in more stable liquid stagnation.
Furthermore, it is preferable the following conditions are satisfied: Ldxe2x89xa60.7Le, wherein a thickness of the flow-resistance layer and an effective length of the tank main body are defined by Ld and Le, respectively. In this case, enough space for accumulating a gaseous refrigerant and a liquefied refrigerant above the tank main body can be secured, resulting in a more stable supply of a liquefied refrigerant.
Furthermore, in the present invention, it is preferable that a filter layer us disposed on at least an upper surface of the desiccant-filled-layer, or a pair of perforated plates are disposed on upper and lower surfaces of the desiccant-filled-layer. In this case, the refrigerant passing through the filter layer or the perforated plates is rectified by the filter layer or the perforated plates. Thus, a partial high-speed flow will be extinguished, and a liquefied refrigerant and a gaseous refrigerant will be divided into minute refrigerant. Accordingly, the liquid stagnation in the upper space can be created stably.
Furthermore, in the present invention, it is preferable that inlets are disposed at predetermined circumferential intervals. In this case, a refrigerant can be introduced into the tank main body evenly from the periphery of the bottom wall of the tank main body, which can assuredly prevent the generation of bubbles of refrigerant due to the turbulence or the like. As a result, stable liquid stagnation can be created.
According to a second aspect of the present invention, a receiver-tank for use in a refrigeration cycle, wherein a condensed refrigerant is introduced into the receiver-tank and accumulated therein and only a liquefied refrigerant flows out of the receiver-tank, the receiver-tank comprises:
a tank main body having a refrigerant inlet and a refrigerant outlet each provided in a bottom wall of the tank main body;
a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer, the flow-resistance layer being provided in the tank main body such that an upper space is formed above the flow-resistance layer;
a suction pipe provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the refrigerant outlet; and
a desiccating-agent-filled member disposed in the upper space so as to space apart from the flow-resistance layer,
whereby a refrigerant introduced into the tank main body via the refrigerant inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the refrigerant outlet via the suction pipe.
According to the second aspect of the present invention, in the same manner as in the first aspect of the present invention, since only the liquefied refrigerant stably flows out from the receiver-dryer, it becomes possible to fill an appropriate amount of the refrigerant in the refrigeration cycle at an earlier stage. Moreover, since the steady region between the optimum point and the excessive point of refrigerant amount can be expanded by using the surplus space in the receiver-dryer as a buffer space, the whole refrigeration cycle can be operated stably.
Furthermore, since the desiccating-agent-filled member is formed in the upper space in the tank main body, the moisture of the refrigerant passing through the tank main body can be deleted. Thus, an appropriate refrigerant with no moisture can be discharged, resulting in a stable operation of the entire refrigeration cycle.
In the second aspect of the present invention, it is preferable that the flow-resistance layer maybe formed by numerous particles, knitted fabrics, woven fabrics, non-woven fabrics, a porous or perforated panel/member or the lamination thereof, or a combination of one or more of the aforementioned members/materials, or the flow-resistance layer is provided with a plurality of dispersing passages for dispersing the refrigerant in a radial and outward direction of the tank main body.
Furthermore, in the second aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents. In this case, it becomes possible to supply an enough amount of desiccating agents as the flow-resistance layer and the desiccating-agent-filled member.
In the second aspect of the present invention, it is preferable that desiccating-agent-filled member is immovably disposed or movably disposed in the upper space.
Furthermore, in the second aspect of the present invention, it is preferable that the following conditions are satisfied: Ld less than D, wherein a thickness of the desiccating-agent-filled member and an inner diameter of the tank main body are defined by Ld and D, respectively. In this case, an enough space for accumulating the liquefied refrigerant and the gaseous refrigerant above the tank main body can be secured, resulting in a steady supply of liquefied refrigerant.
Furthermore, in the second aspect of the present invention, it is preferable that a lower space for diffusing the refrigerant introduced from the refrigerant inlet is formed under the flow-resistance-layer in the tank main body. In this case, the refrigerant introduced from the refrigerant inlet diffuses widely in the lower space, resulting in a reduced flow velocity. Thus, generation of turbulence in the lower space can be prevented more assuredly, which enables to create stable liquid stagnation.
Furthermore, in the second aspect of the present invention, it is preferable that the refrigerant outlet is formed at a center of the bottom wall of the tank main body and a plurality of the refrigerant inlets are formed around the refrigerant outlet. In this case, it becomes possible to introduce a refrigerant into the tank main body from the peripheral portion of the bottom of the tank main body in a dispersed manner. Thus, generation of bubbles due to a biased flow and/or turbulence of refrigerant can be effectively prevented, which enables to create further stable liquid stagnation.
Furthermore, in the second aspect of the present invention, it is preferable that the plurality of the refrigerant inlets are disposed at predetermined circumferential intervals. In this case, the refrigerant can be introduced evenly into the tank main body from the peripheral portion of the bottom wall of the tank main body. Thus, generation of bubbles due to a biased flow and/or turbulence of refrigerant can be effectively prevented, which enables to create further stable liquid stagnation.
On the other hand, the aforementioned receiver-tank according to the first aspect of the present invention can be integrally assembled to a heat exchanger such as a condenser to form a heat exchanger with a receiver-tank.
According to a third aspect of the present invention, a heat exchanger with a receiver-tank, comprises:
a heat exchanger body including a pair of headers disposed in parallel at a certain distance, a plurality of heat exchanging tubes with both ends thereof connected to the pair of headers and a condensing portion outlet for discharging a refrigerant condensed while passing through the heat exchanging tubes;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of the receiver-tank, the receiver-tank accumulating a refrigerant introduced from the receiver-tank inlet and discharging only a liquefied refrigerant from the receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant flowed out of the condensing portion outlet into the receiver-tank inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer is provided in the receiver-tank such that an upper space is formed above the flow-resistance layer,
wherein a suction pipe is provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the refrigerant outlet,
whereby a refrigerant introduced into the tank main body via the refrigerant inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the refrigerant outlet via the suction pipe.
In the third aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents, or a lower space for diffusing the refrigerant introduced from the refrigerant inlet is formed under the flow-resistance-layer in the tank main body.
Furthermore, the receiver-tank according to the first aspect of the present invention can be integrally assembled to a heat exchanger having a condensing portion and a subcooling portion to form a heart exchanger with a receiver-tank such as a subcooling system condenser.
According to the fourth aspect of the present invention, a heat exchanger with a receiver-tank, comprises:
a heat exchanger body including a pair of headers disposed in parallel at a certain distance, a plurality of heat exchanging tubes with both ends thereof connected to the pair of headers, partitioning members each partitioning an inside of the header to thereby group the plurality of heat exchanging tubes into a condensing portion and a subcooling portion, a condensing portion outlet for discharging a refrigerant condensed while passing through the heat exchanging tubes and a subcooling portion inlet for introducing a refrigerant into the subcooling portion;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of the receiver-tank, the receiver-tank accumulating a refrigerant introduced from the receiver-tank inlet and discharging only a liquefied refrigerant from the receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant discharged from the condensing portion outlet into the receiver-tank inlet and introducing the refrigerant discharged from the receiver-tank outlet into the subcooling portion inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer is provided in the receiver-tank such that an upper space is formed above the flow-resistance layer, and
wherein a suction pipe provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the refrigerant outlet,
whereby a refrigerant introduced into the tank main body via the receiver-tank inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the receiver-tank outlet via the suction pipe.
In the fourth aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents.
According to the fifth aspect of the present invention, a heat exchanger with a receiver-tank, comprising:
a heat exchanger body including a pair of headers disposed in parallel at a certain distance, a plurality of heat exchanging tubes with both ends thereof connected to the pair of headers and a condensing portion outlet for discharging a refrigerant condensed while passing through the heat exchanging tubes;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of the receiver-tank, the receiver-tank accumulating a refrigerant introduced from the receiver-tank inlet and discharging only a liquefied refrigerant from the receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant flowed out of the condensing portion outlet into the receiver-tank inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer is provided in the receiver-tank such that an upper space is formed above the flow-resistance layer,
wherein a suction pipe is provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the receiver-tank outlet, and
wherein a desiccating-agent-filled member is disposed in the upper space so as to space apart from the flow-resistance layer,
whereby a refrigerant introduced into the tank main body via the receiver-tank inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the receiver-tank outlet via the suction pipe.
In the fifth aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents.
Furthermore, in the fifth aspect of the present invention, it is preferable that desiccating-agent-filled member is immovably or movably disposed in the upper space.
The receiver-tank according to the second aspect of the present invention can be integrally assembled to a heat exchanger having a condensing portion and a subcooling portion to form a heat exchanger with a receiver-tank such as a subcooling system condenser.
According to the sixth aspect of the present invention, a heat exchanger with a receiver-tank, comprising:
a heat exchanger body including a pair of headers disposed in parallel at a certain distance, a plurality of heat exchanging tubes with both ends thereof connected to the pair of headers, partitioning members each partitioning an inside of the header to thereby group the plurality of heat exchanging tubes into a condensing portion and a subcooling portion, a condensing portion outlet for discharging a refrigerant condensed while passing through the heat exchanging tubes and a subcooling portion inlet for introducing the refrigerant into the subcooling portion;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of the receiver-tank, the receiver-tank accumulating a refrigerant introduced from the receiver-tank inlet and discharging only a liquefied refrigerant from the receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant discharged from the condensing portion outlet into the receiver-tank inlet and introducing the refrigerant discharged from the receiver-tank outlet into the subcooling portion inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer is provided in the receiver-tank such that an upper space is formed above the flow-resistance layer,
wherein a suction pipe is provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the receiver-tank outlet, and
wherein a desiccating-agent-filled member is disposed in the upper space so as to space apart from the flow-resistance layer,
whereby a refrigerant introduced into the tank main body via the receiver-tank inlet passes through the flow-resistance. layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows out of the receiver-tank outlet via the suction pipe.
In the sixth aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by numerous particle-shaped desiccating agents.
The receiver-tank according to the first aspect of the present invention can constitute a condensing apparatus for use in a refrigeration cycle together with a condenser such as a header-type condenser and a serpentine-type condenser.
According to a seventh aspect of the present invention, a condensing apparatus for use in a refrigeration cycle, the condensing apparatus comprises:
a condenser including a condensing portion for condensing a refrigerant and a condensing portion outlet for discharging the refrigerant condensed by the condensing portion;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of the receiver-tank, the receiver-tank accumulating a refrigerant introduced from the receiver-tank inlet and discharging only a liquefied refrigerant from the receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant flowed out of the condensing portion outlet into the receiver-tank inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through the flow-resistance layer is provided in the receiver-tank such that an upper space is formed above the flow-resistance layer, and
wherein a suction pipe is provided in the tank main body, the suction pipe having an upper end opened toward the upper space and a lower end communicated with the receiver-tank outlet,
whereby a refrigerant introduced into the tank main body via the receiver-tank inlet passes through the flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in the upper space, and the liquefied refrigerant flows cut of the receiver-tank outlet via the suction pipe.
Furthermore, the receiver-tank according to the second aspect of the present invention can constitute a condensing apparatus for use in a refrigeration cycle together with a condenser such as a header-type condenser and a serpentine-type condenser.
According to the eighth aspect of the present invention, a condensing apparatus for use in a refrigeration cycle, said condensing apparatus comprising:
a condenser including a condensing portion for condensing a refrigerant and a condensing portion outlet for discharging the refrigerant condensed by said condensing portion;
a receiver-tank having a receiver-tank inlet and a receiver-tank outlet each formed in a bottom wall of said receiver-tank, said receiver-tank accumulating a refrigerant introduced from said receiver-tank inlet and discharging only a liquefied refrigerant from said receiver-tank outlet; and
a refrigerant passage for introducing the refrigerant flowed out of said condensing portion outlet into said receiver-tank inlet,
wherein a flow-resistance layer for reducing a flow velocity of a refrigerant passing through said flow-resistance layer is provided in said receiver-tank such that an upper space is formed above said flow-resistance layer,
wherein a suction pipe is provided in said tank main body, said suction pipe having an upper end opened toward said upper space and a lower end communicated with said receiver-tank outlet, and
wherein a desiccating-agent-filled member is disposed in said upper space so as to space apart from said flow-resistance layer,
whereby a refrigerant introduced into said tank main body via said receiver-tank inlet passes through said flow-resistance layer upward to cause liquid stagnation of a liquefied refrigerant in said upper space, and the liquefied refrigerant flows out of said receiver-tank outlet via said suction pipe.
In the eighth aspect of the present invention, it is preferable that the flow-resistance layer is a desiccant-filled-layer constituted by particle-shaped desiccating agents.
Other objects and the features will be apparent from the following detailed description of the present invention with reference to the attached drawings.